3rd International Conference

3rd International Conference
and
3rd International Trade Fair
of Geodesy, Cartography, Navigation and Geoinformatics
GEOS 2008
Conference Proceedings – Full Text
Prague / Czech Republic, 27th – 28th February 2008
under the auspices of the Chief of the Geographic Service of the Army
of the Czech Republic
colonel Ing. Pavel Skála
edited by Milan Talich
Milan Talich (Ed.)
GEOS 2008, 3rd International Conference and 3rd International Trade Fair of Geodesy,
Cartography, Navigation and Geoinformatics
Full text: www.vugtk.cz/geos/2008
Technical editing: Filip Antoš
Part of the abstracts and preamble translation: Jan Rambousek, Jitka Jurková
Printed in Czech and English
Prague, Czech Republic
February 2008
VÚGTK, v.v.i. Volume 54 Publication No. 44
Reaserch Institute of Geodesy,
Topography and Cartography (VÚGTK, v.v.i.)
Ústecka 98, CZ – 250 66 Zdiby
Czech Republic
Tel +420 284 890 351
Fax +420 284 890 056
Email: [email protected]
Web: www.vugtk.cz
ISBN 978-80-85881-29-5
Vážení čtenáři,
opět se vám dostává do rukou sborník z mezinárodní konference geodézie, kartografie, navigace
a geoinformatiky, tentokráte GEOS 2008, konané pod heslem „Naše profese v Evropě bez hranic“
a pod záštitou náčelníka Geografické služby AČR plk. Ing. Pavla Skály.
Konference GEOS 2008 si klade za cíl stejně jako v předchozích letech podchytit novinky a vývojové
trendy ve všech specializacích našeho oboru. Vzhledem k většímu rozšíření schengenského prostoru
koncem loňského roku, bylo zvoleno právě motto, které více reflektuje tuto novou situaci v Evropě.
Konference se tak věnuje nejen již tradičním tématům, jako jsou geoinformace a GIS, kartografie
a mapová tvorba, navigační systémy a služby založené na lokaci, geodetické základy a geodetické
práce, katastr nemovitostí, fotogrammetrie a dálkový průzkum. Ale zaměřuje svou pozornost také na
oblasti pohybu zeměměřičů v evropském prostoru, uznávání kvalifikací pro výkon zeměměřických
činností, požadavky na vzdělávání zeměměřičů a zajišťování kvality zeměměřických prací.
V roce 2008 je konference oproti předchozím letům vyjímečná v tom, že bezprostředně předchází
zasedání valného shromáždění Rady evropských zeměměřičů (CLGE), které se koná v Praze
v následujících dvou dnech. Motto konference je navíc velice blízké i tématům, kterým se CLGE
dlouhodobě věnuje.
Kromě zmíněného zasedání valného shromáždění CLGE probíhá ještě souběžně s konferencí v Praze
ve dnech 28. 2. až 1. 3. též 3. mezinárodní veletrh geodézie, kartografie, navigace a geoinformatiky
GEOS, který také stojí za shlédnutí.
Únor 2008
Milan Talich
odborný garant konference
Dear reader,
this year again you receive in your hands proceedings from the International Conference of Geodesy,
Cartography, Navigation and Geoinformatics GEOS 2008 held under the motto „Our profession
in Europe without Barriers“ and under auspices of the Chief of the Geographic Service of the Army
of the Czech Republic colonel Ing. Pavel Skála.
The main task of conference GEOS 2008 is, similarly to the previous years, to follow news
and development trends in all specializations of our field. Regarding the enlargement of Schengen
territory at the end of 2007, we decided to choose the above mentioned motto as it reflects this new
situation in Europe. Therefore the conference focuses not only on traditional subjects,
e.g. geoinformatics and GIS, cartography and mapping, navigation systems and services based
on location, basic geodetic control and geodetic work, cadastre of real estate, photogrammetry
and remote sensing, but also on the scope of surveyors´ movement within the territory of Europe,
recognizing qualifications and education requirements for land surveyors and controlling the quality
of land surveying.
In comparison with previous years, conference GEOS 2008 is exceptional as it is held immediately
before the General Assembly Meeting of the Council of European Geodetic Surveyors (CLGE) that
takes place in Prague in the following two days. In addition, the conference motto is very close to the
subjects that are of long-term interest of CLGE.
Besides the above mentioned General Assembly Meeting of CLGE, at the same time
as the conference, the 3rd International Fair of Geodesy, Cartography, Navigation and Geoinformatics
GEOS (that is worth seeing as well) takes place in Prague from 28 February to 1 March 2008.
February 2008
Milan Talich
Professional Warranter of the Conference
Contents / Obsah
Basic Geodetic Control Not Only for Navigation Systems and Services Based on Location / Geodetické základy nejen pro navigační
systémy a služby založené na lokaci
Gerd Rosenthal, Anette Blaser, Jaroslav Šimek:
EUPOS – Regionální infrastruktura pro určování polohy pomocí GNSS v zemích střední a východní Evropy – stav na přelomu
let 2007/2008
EUPOS – Regional GNSS Positioning Infrastructure for Central and Eastern Europe – Status 2007/2008 ...................................................... 1
Marcin Ryczywolski, Artur Oruba, Marcin Leończyk:
The Precise Satellite Positioning System ASG-EUPOS
Přesný družicový polohový system ASG-EUPOS.................................................................................................................................. 18
G.Silabriedis, S.Plotnikov, J.Balodis:
The EUPOS-RIGA Application for Mapping Control
Užití EUPOS – RIGA pro mapovací kontrolu ........................................................................................................................................ 24
M.Premužić, M. Kekić, M. Marjanović, M. Bosiljevac, B. Slevka:
CROPOS (Croatian Positioning System)
CROPOS (Chorvatská polohová soustava) ......................................................................................................................................... 33
Basic Geodetic Control and Geodetic Work CZEPOS / Geodetické základy a geodetické práce CZEPOS
Jan Řezníček:
CZEPOS – Současný stav
CZEPOS – Present State .................................................................................................................................................................. 40
Vratislav Filler:
Testováni stability stanic GNSS na území ČR v místním analytickém centru GO Pecný
Test of Stability GNSS Sites on Czech Republic Area by Local Analysis Centre GO Pecný ........................................................................ 44
Miluše Vilímková:
Analýza časových řad souřadnicových změn v CZEPOS
Analysis of theTime Series of Coordinates of theCZEPOS ..................................................................................................................... 51
Jaroslav Nágl:
Zkušenosti s modelováním troposféry v sítích APOS a CZEPOS
Experience with Troposphere Modelling by APOS and CZEPOS Networks .............................................................................................. 56
Basic Geodetic Control and Geodetic Work / Geodetické základy a geodetické práce
Dušan Ferianc, Elena Šalátová:
Geodetické základy Slovenska v roku 2008
Geodetic Control of Slovakia in Year 2008 ........................................................................................................................................... 61
Gerd Boedecker:
On Gravity Standardisation and the Unified European Gravity Reference Network UEGN02
O normalizaci tíže a jednotné evropské referenční tíhové síti UEGN02 .................................................................................................... 68
Martin Kadlec, Pavel Novák:
Porovnání metod pro výpočet terénních korekcí pro území střední Evropy
Comparison of Different Methods for Evaluation of Terrain Corrections for the Area of Central Europe ......................................................... 75
Valerio Baiocchi, Paola Capaldo, Mattia Crespi, Marco Mezzapesa, Grazia Pietrantonio:
Calibration of Geoid Models in Colli Albani Area (Rome, Italy)
Kalibrace modelů geoidu v oblasti Colli Albani (Řím, Itálie)..................................................................................................................... 87
Navigation Systems and Services Based on Location / Navigační systémy a služby založené na lokaci
Miloš Cimbálník:
Souřadnicové systémy na území České republiky
Co-ordinate Systems On the Czech Republic Territory .......................................................................................................................... 92
Pavel Vaniš, Pavel Tesař:
Webová služba VÚGTK pro transformaci mezi WGS-84 a S-JTSK
Web Service of VÚGTK for Transformation between WGS-84 andS-JTSK ............................................................................................. 124
Pavel Taraba:
Současné možnosti geodetických měření v sítích permanentních stanic GNSS v ČR
Current Possibilities of Land Survey in Networks of GNSS Permanent Stations in the Czech Republic ....................................................... 131
Reiner Jäger, Simone Kälber:
The New RTCM 3.1 Transformation Messages – Declaration, Generation from Reference Transformations and Implementation
as a Server-Client-Concept for GNSS Services
Nové transformační zprávy RTCM 3.1 - prohlášení, vytváření z referenčních transformací a zavádění jako pojetí server-klient-koncept
pro služby GNSS ........................................................................................................................................................................... 138
Geoinformation and GIS, Cartography and Map Creation / Geoinformace a GIS, kartografie a mapová tvorba
Milan Kocáb, Milan Talich:
Webové aplikace pro zeměměřiče
Web applications for Surveyors ............................................................................................................................................................ 159
Hui Lin, Jun Zhu, Bingli Xu:
A Study on the Particle System Method for Dynamic Modelling in Virtual Geographic Environments (VGE)
Studie o metodě částic pro dynamické modelování ve virtuálním geografickém prostředí (VGE)............................................................................ 174
Ljerka Rašić, Siniša Hofer, Ivana Šimat:
Reflection of new geodetic datum and map projection intoduction on orthophoto production process
Dopad nového geodetického počátku a mapového zobrazení na ortofotografický výrobní postup ........................................................................... 179
Lucie Stavařová:
Vytvoření interaktivní 3d vizualizace vybraného území
The Creation of the Interactive 3d Visualization of the Elected Area .............................................................................................................. 188
V. Gershenzon, E. Ash:
ScanEx R&D Center Projects
Projekty centra ScanEx R&D .............................................................................................................................................................. 194
Our Profession in Europe without Barriers / Naše profese v Evropě bez hranic
Jiří Šíma:
Zeměměřictví a katastr nemovitostí v České republice na prahu 21. století
Surveying, Mapping and Cadastre in the Czech Republic at the Beginning of 21st Century .................................................................................. 197
Alain Gaudet, Michel Patrick Lagoutte, Rafic Khouri:
The Latest Developments in Educational Standards in France
Nejnovější vývoj požadavků na vzdělání ve Francii ................................................................................................................................... 205
Václav Slaboch:
Vyhovuje kvalifikace úředně oprávněných zeměměřičů v Česku požadavkům evropských profesních organizací?
Does the Professional Qualification of the Public Appointed Surveyors in Czechia Satisfies the Requirements of the European Professional
Organisations? ................................................................................................................................................................................ 213
Vladimír Stromček:
Kontakty slovenských geodetov s Európou
Slovak Surveyors Contacts with Europe ................................................................................................................................................. 227
Zdeněk Fišer, Miloslav Švec, Petr Kalvoda, Jiří Vondrák:
Výuka Katastru nemovitostí a Mapování v Brně
Education of Real Estate Cadastre and Mapping in Brno ............................................................................................................................ 228
Tomáš Cajthaml:
Platforma pro zajištění kvality v národních mapovacích a katastrálních službách
Quality Assurance Platform in National Mapping and Cadastral Agencies ...................................................................................................... 233
Emmanuel Ouranos:
Prevention and Management of Physical Disasters and the Surveyor ‘s Involvement
Prevence a zvládání fyzikálních kalamit a zeměměřičovo zapojení ................................................................................................................. 243
Pavla Tryhubová:
Analýza dopadů směrnice inspire na informační obsah ZABAGED
Analysis of Inspire Directive Impacts on Information Contents Of ZABAGED .................................................................................................. 246
Eva Mičietová, Juraj Vališ:
Distribúcia geografických informácií vo vsťahu k INSPIRE – súčasný stav v SR
Distribution of Geographic Information in Relation to INSPIRE – Current Condition in SR ................................................................................. 257
Adrian Traian Radulescu, Gheorghe M.T. Radulescu:
Upon a National Concept of GIS as Basis of the Strategy for Integration in the Euro-Atlantic Structures, the Case Study of the
Baia Mare Municipality
O národním pojetÍ GIS coby základny strategie integrace do Euro-Atlantických struktur, příkladová studie obce Baia Mare ........................................ 271
Cadastre of Real Estate / Katastr nemovitostí
Gabriel Bădescu:
RTK (Real-Time Kinematics) – GPS Technology with Data Transmission through UHF Radio Waves, Used in Cadastre
RTK (kinematika v reálném čase) – technologie GPS užitá v katastru s přenosem dat pomocí radiových vln UHF ..................................................... 279
Vít Suchánek:
Katastr nemovitostí ČR
Cadastre of Real Estates of the Czech Republic ........................................................................................................................................ 288
Jiří Poláček:
Služby a produkty informačního systému katastru nemovitostí
Services and Products of the Information Systém of Cadastre of Real Estates ................................................................................................... 299
Anna Ilieva, Yordanka Mizova:
Elaboration of the Cadastral Plan for the Town of Pazardzhik
Vytvoření katastrálního plánu města Pazardžik ........................................................................................................................................ 307
Cadastre of Real Estate, Photogrammetry and Remote Sensing / Katastr nemovitostí, Fotogrammetrie a dálkový průzkum
Jana Zaoralová:
Zpracování pozemkových úprav v novém výměnném formátu
Land Adaptation Processing in New Exchange Format .............................................................................................................................. 311
Luís Miguel Cotrim Mateus:
Evaluating a Low Cost Photogrammetry Method with 3d Laserscanning
Vyhodnocení fotogrammetrické metody s nízkými náklady a trojrozměrným laserovým skenováním ....................................................................... 317
Jan Řezníček:
Tvorba sítě a zhlazení mračna bodů z dat laserového skenování metodou zobrazení bodů do roviny
Triangulation and Smoothing of Terrestrial Laserscanner Dataset by Using Method of Point Projection from 3D to a 2D (Plane) ................................. 327
Lubomír Soukup:
Vlícování pomocí identických přímek
Matching by Ground Control Lines ....................................................................................................................................................... 331
List of Posters / Seznam posterů
Gabriel Bădescu:
Comparative Study Concerning the Transformation of Coordinates Determined Using GNSS Technology, into the STEREO 70
Projection System
Srovnávací studie transformace souřadnic určených technologií GNSS do projekčního systému STEREO 70 ............................................................ 332
Haddad Mahdi, Abdellaoui Hassen:
Algerian Permanent GPS Network: Comparison of Results Obtained by the Bernese 5.0 Software in Interactive and Automatic
Mode
Alžírská stálá síť GPS : Srovnání výsledků získaných softwarem BERNESE 5.0 v interaktivním a automatickém módu ................................................ 338
Jindřich Hodač:
Fotogrammetrická dokumentace historických objektů – jednoduché metody
Photogrammetric Documentaion of Historical Sites – Simple Methods ........................................................................................................... 342
Adrian Traian Radulescu, Gheorghe M.T. Radulescu, Ovidiu Stefan:
As Means to Assure Structure Safety- Dynamic Surveying
Zajištění bezpečnosti stavby – dynamické měření ...................................................................................................................................... 349
Petr Skála:
Jak poznat dobrou zeměměřickou kancelář?
How Recognise a Good Geodetic Office? ............................................................................................................................................... 363
Pavel Tesař:
NTRIP – využití IP multicastingu
NTRIP – Using of IP Multicasting ........................................................................................................................................................ 371
Lenka Vlčková:
Optimalizace horizontu v lokalitě hvězdárny a planetária Johanna Palisy v Ostravě
Optimalization of Horizont in Observatory and Planetarium of Johann Palisa in Ostrava ................................................................................... 372
Jaroslava Kraftová:
Vývoj, význam a rozvoj inženýrské geodézie
Trend, value and development of engineering geodesy ............................................................................................................................... 378
Evaluating a low cost photogrammetry method with 3D laser scanning
GEOS 2008
EVALUATING A LOW COST PHOTOGRAMMETRY METHOD WITH
3D LASER SCANNING
Luís Miguel Cotrim Mateus, Architect (Ph.D Student)
Department of Architecture, Faculty of Architecture,
Thecnical University of Lisbon, Rua Sá Nogueira, Pólo Universitário - Alto da Ajuda, PORTUGAL
e-mail: [email protected]
Abstract
The aim of this paper is to evaluate the results obtained with the application of a low cost
photogrametric method to architectural surveying. The development is part of a PhD research project.
The referred method was developed and implemented using Autolisp Language Programming for
AutoCAD and was tested on surveying façades and exterior boundaries (plan) of a well geometrically
defined building. This building is a Renaissant XVIth century church. The method will be described
and explained and the study case will be presented as well as the obtained results.
Then, the results will be compared to a 3D laser scanning surveying of the same building. This
surveying was performed with a Z+F Scanner Imager 5006. Assuming 3D laser scanning as an
accurate surveying method for the global geometry of the building, façade and plan drawings obtained
from this data will be the base for comparison.
This is a low cost method and is accessible to non experts in surveying as in general architects
are and can provide reliable data for some architectural applications that do not evolve structural
changes in buildings. It can also be used as a complementary method for other surveying methods both
in professional or academic context.
1 Introduction
To building surveying, for architectural purposes, many strategies may be adopted. Some are
more practical and rapid and others are slower. Some may require experts and other don’t. We must
always consider de adequacy of the chosen strategy with surveying purpose.
The method here presented that can be defined as an elementary photogrammetric method can
be applied to the survey of buildings with approximately contiguous plane façades. Its operative base
consists on three steps: a) drawing rectification, b) angle determination between façades, and c) angle
registration. All these steps take place within AutoCAD working environment on drawings produced
over inserted images. It is required that one vertical and one horizontal measurement be taken from
each façade. In practice only one vertical measurement is needed over the entire exterior of the
building.
First step consists on the rectification of vectorial drawing, rather than image, produced over
one or more inserted pictures of the façade.
Second and third steps consist on producing, with a minimum effort in field work, the plan of
the exterior boundary of the building. This is applicable when the building presents multiple
contiguous façades. This may me of interest if we don’t have access to the interior of the building and
its boundary presents convex angles. Third step is done manually.
It is not intended to defend the efficiency of this method with respect to others, but to point out
that it can be used as a complement of other surveying methods.
To make this set of procedures operative it was programmed two routines in AutoLisp.
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2 Drawing rectification
As it was referred, first step of the method consists on drawing rectification. This corresponds
to a projective transformation that can de defined as follows:
Xu =
Yu =
e1 xn + f1 yn + g1
e0 xn + f 0 yn + 1
e2 xn + f 2 yn + g 2
e0 xn + f 0 yn + 1
Where:
X u and Yu are the coordinates of the unknown point Pu ,
xn and yn are the coordinates of the known point Pn corresponding to the unknown
point Pu ,
e0 , e1 , e2 , f 0 , f1 , f 2 , g1 , g 2 are the eight parameters of the projective
transformation.
It is known that four Pn points and the corresponding four Pu points are required to determine
the eight parameters of the projective transformation. In practice this means that a minimum of to
measurements must be done: height and width.
Let Pi ( i = {1,2,3,4}), of coordinates X i and Yi , and P'i ( i = {1,2,3,4}), of coordinates xi
and yi , be corresponding points under the projective transformation. The points P'i are associated
with the points Pn , of coordinates xn and yn , of the figure ff that are to be transformed into the
points Pu , of coordinates X u and Yu , of the figure FF .
If three of the eight coordinates of the points Pi are equal to 0 , and three of the eight
coordinates of the points P'i are equal to 0 , then the eight projective parameters are easy to calculate.
In general this condition is not in principle fulfilled.
In order to perform the projective transformation fulfilling this condition a set of other
transformations must be carried out:
a) A translation according to the vector P4O is applied to the points Pi ( i = {1,2,3,4}), of
coordinates X i and Yi , in order to get the points Pit , of coordinates X it and Yit , according to the
following expressions:
X it = X i − X 4
Yit = Yi − Y4
b) A translation according to the vector P '1 O is applied to the points P'i ( i =
{1,2,3,4}), of
coordinates xi and yi , and to the points Pn , of coordinates xn and yn , of the figure ff , in order to
get the points P'it , of coordinates xit and yit , and the points Pnt , of coordinates xnt and ynt , of the
figure fft , according to the following expressions:
xit = xi − x1
yit = yi − y1
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xnt = xn − x1
ynt = yn − y1
c) A rotation is applied to the points Pit centred in the origin in order to align the vector P4 t P3t
with xx axis, getting the points Pitr of coordinates X itr and Yitr , according to the following
expressions:
X itr = X it cos α + Yit sin α
Yitr = − X it sin α + Yit cos α
Where:
cos α =
sin α = −
X 3t
X 32t + Y32t
Y3t
X 32t + Y32t
d) A rotation is applied to the points P'it and to the points Pnt of the figure fft , centred in the
origin in order to align the vector P '1t P '2t with the axis xx , getting the points P'itr of coordinates
xitr and yitr and the points Pntr , of the figure ff tr , of coordinates xntr and yntr , according to the
following expressions:
xitr = xit cos β + yit sin β
yitr = − xit sin β + yit cos β
xntr = xnt cos α + y nt sin β
y ntr = − xnt sin β + y nt cos β
Where:
cos β =
sin β = −
x2t
x22t + y 22t
y 2t
x + y 22t
2
2t
e) After these transformations we have four points Pitr and four corresponding points P'itr
under an auxiliary projective transformation. The eight parameters of this projective transformation,
e'0 , e'1 , e'2 , f '0 , f '1 , f '2 , g '1 , g '2 can be easily calculated:
g '1 = X 1tr
g '2 = Y1tr
f '2 =
Y1tr x4tr − Y1tr x3tr
x3tr y4tr − y3tr x4tr
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L. Mateus
e '2 =
Y1tr y3tr − Y1tr y4tr
x3tr y4tr − y3tr x4tr
e'1 =
e'2 X 2tr X 2tr (Y1tr − Y2tr ) X 1tr − X 2tr
+
−
Y2tr
x2trY2tr
x2tr
f '1 = −
e'0 =
e'1 x4tr + X 1tr
y4tr
e'2 Y1tr − Y2tr
+
Y2tr
x2trY2tr
f '0 =
e'1 x3tr + f '1 y3tr + X 1tr − e'0 x3tr X 3tr − X 3tr
y3tr X 3tr
f) Now a projective transformation can be applied to the points Pntr , of coordinates xntr and
yntr , of the figure ff tr , in order to get the corresponding points points Putr , of coordinates X utr and
Yutr , of the figure FFtr , according to the following expressions:
X utr =
Yutr =
e'1 xntr + f '1 yntr + g '1
e'0 xntr + f '0 yntr + 1
e'2 xntr + f '2 yntr + g '2
e'0 xntr + f '0 yntr + 1
g) A rotation is applied to the points Putr , of coordinates X utr and Yutr , of the figure FFtr ,
centred in the origin and symmetric to the one applied in c), getting the points Put , of coordinates X ut
and Yut , of the figure FFt , according to the following expressions:
X ut = X utr cos(−α ) + Yutr sin( −α )
Yut = − X utr sin(−α ) + Yutr cos(−α )
Where:
cos(−α ) = cos α =
sin( −α ) = − sin α =
X 3t
X 32t + Y32t
Y3t
X 32t + Y32t
h) Finally, a translation is applied to the points Put , of coordinates X ut and Yut , of the figure
FFt , according to the vector OP4 , getting the points Pu , of coordinates X u and Yu , of the figure
FF , corresponding to the points of the initial figure ff , according to the following expressions:
X u = X ut + X 4
Yu = Yut + Y4
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3 Angle determination between façades
In order to perform this operation, photograph must be taken horizontally and a minimum of
three measurements must be carried out in-sittu, VC , De and Dd . To simplify the process it is
supposed that a rectangle corresponding to the measurements taken can be drawn over the image in
each façade as shown in fig. 1. Then, by selecting the segments VC , Ve e Vd in the picture and the
segments VC ' , De and Dd drawn apart , angle between both façades can be calculated.
Fig. 1
This determination relies on the following.
Let us consider the right façade in fig. 1.
Let Dd K = [OB ] = R , where K is a scale factor determined by:
K=
VC
VC '
Let [ON ] be the distance, taken over the photo, between verticals VC and Vd .
Let A be any point in the right façade (in practice this point doesn’t have to be identified by
the operator; it can be assumed as the crossing point between rectangle diagonals).
Let M be, in the image, the corresponding point to the point A (in practice this point doesn’t
has to be identified by the operator; logically it has to be the crossing point of the trapezium diagonals)
On fig. 2 xx axis corresponds to the image plan.
The angle α that right façade does with picture plan is undetermined. However it is known
that the projecting rays A.M and B.N cross at the projection centre P as shown in fig. 2.
Let the coordinates of the points A , B , M ,
N and P be as follows:
A = ( r cos α ; r sin α )
B = ( R cos α ; R sin α )
M = ( d ;0)
N = ( D;0)
P = ( X P ; YP )
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L. Mateus
y
B
R
A
r
α
O
M
N
x
C
P
[c]
Fig. 2
The alignments A.M .P e B.N .P can be expressed by:
r cos α
r sin α
1
d
0
1
R cos α
R sin α
D
0
1
1
XP
YP = 0
1
XP
YP = 0
1
From this one can determine X P e YP , as follows:
Rr ( d − D )
sin α
Rd − rD
Rr ( d − D )
Dd ( R − r )
XP =
cos α +
Rd − rD
Rd − rD
YP =
⎛ Dd ( R − r ) ⎞
;0 ⎟ and
⎝ Rd − rD ⎠
These express the parametric equations of a circle [c] with centre C = ⎜
radius R[C ] =
Rr ( d − D )
.
Rd − rD
Proceeding In an analogous way to the left façade one can determine a circle [e] with centre
E and radius R[E ] as show in fig. 3.
The centre of projection P that allows to reconstruct simultaneously the geometry derived
from the projection of both façade planes is one of the intersection points of the two circles [c] and
[e] .
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Like this one can determine the angle π between both façades refered to the dimensions
De K and Dd K . Scale factor can then be eliminated dividing boht values with K .
Q
y
B
DeK
DdK
π
E
N
O
P
x
C
[c]
[e]
Fig. 3
4 The case study
As referred, the surveying method described was implemented with AutoLisp Programming
Language for AutoCad. Then the principal façade and exterior boundary of a Renaissant XVIth
century church were surveyed to test the application.
Fig. 4
To façade drawing some assumptions were made that may not be correct. It was assumed that
left and right limits of the façade are vertical, and that the upper limit is horizontal. Control measures
were taken with metric tape.
Fig. 4 represents façade surveying and fig. 5 represents boundary surveying.
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L. Mateus
Fig. 5
5 Evaluation with 3D laser scanning and conclusions
After the previous step was completed, a 3D laser scanning survey of the church was carried
out with a Z+F scanner Imager 5006, by the company 3D Total. From the 3d model obtained it was
produced a horizontal section and a façade ortho-image with RGB values assigned.
These two elements served as basis for accuracy verification, by comparison, of the proposed
photogrammetric surveying method. It was assumed that laser scanning provides reliable results.
Two evaluations were done.
First, façade survey was overlapped to the ortho-image both being in the same scale. This
procedure was accomplished identifying two corresponding horizontal lines. In the overlapped
drawing and image this line is identified as L1 and its extremities are identified as P1 and P2 as shown
in fig. 6.
Fig. 6
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GEOS 2008
Then distances between corresponding points were taken. It was observed that in the lower
part of the façade, distances vary within a range of 4cm and that in the upper part of the upper part of
the façade distances vary within a range of 8cm.
These differences can be explained with the assumptions that were made when surveying, with
the control measurements and with the fact that camera distortions were not taken into account.
In an analogous way, the plan survey was overlapped with the section obtained from the 3d
model and discrepancies were measured, as shown in fig. 7.
Fig. 7
In red we have the 3d model section and in black we have the survey carried out with the
present method. The alignment between both surveys was accomplished identifying both lines
corresponding to the principal façade.
Here two verifications were made.
On one hand, it were measured distances between corresponding points. In this case, and for
the selected area, distances vary from 0 to 25cm.
On the other hand, corresponding angles were compared. In this, case and for the selected
area, angles vary from 0 to 2.5º.
These differences can be explained with the assumptions that were made when surveying
(façades being plan), with the control measurements, with the fact that camera distortions were not
taken into account, with the fact that camera axis is not exactly horizontal, and with the fact that the
registration between angles is manual and errors are summed.
With respect to façade surveying, this evaluation shows that the results can be found reliable
for some architectural applications that don’t involve structural changes such as area calculation,
pathology mapping, and stylistic analysis, among others.
With respect to plan surveying the results are more difficult to accept. It is required that
further work is done in order to minimize discrepancies verified. This can consist on the consideration
of camera distortion parameters, a better control while taking the pictures, and a more accurate mean
of to proceed to angle registration.
6 Acknowledgments
The author wants to refer that this work is part of an Investigation Project funded by FCT
(Fundação para a Ciência e Tecnologia). This ID Project is entitled “Architectural Heritage
Conservation: a Methodology to 3D Laser scanning and digital photogrammetry Documentation”
(ref. PTDC/AUR/66476/2006).
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References
[1]
[2]
[3]
[4]
[5]
Feiffer C (1989) Il progetto di conservazione, Franco Angeli Libri s.r.l., Milan
Maestri D and Docci M (2005) Manuale di rilevamento architettonico e urbano, Editori Laterza, Roma
Mateus L (2007) Rectificação de desenho vectorial In: Novas perspectivas em Sistemas e Tecnologias de Informação (CD), edições Universidade Fernando Pessoa,
Porto
Mikhail E, Bethel J and McGlone J (2001) Introduction to Modern Photogrammetry,
John Wiley & Sons, Nova Iorque
AutoLISP Programmers Reference Autocad release 12 (1992) Autodesk BV, Neuchatel
326
GEOS 2008, 3rd International Conference and 3rd International Trade Fair
of Geodesy, Cartography, Navigation and Geoinformatics - proceedings
Edited by Milan Talich
Full text: www.vugtk.cz/geos/2008
Tato publikace neprošla redakční ani jazykovou úpravou.
Technical editing: Filip Antoš
Part of the abstracts and preamble translation: Jan Rambousek, Jitka Jurková
Published by
Výzkumný ústav geodetický, topografický a kartografický (VÚGTK, v.v.i.)
Research Institute of Geodesy, Topography and Cartography
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© VÚGTK, v.v.i. 2008
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